1. Field of the Invention
This invention relates to an automatic polarization analysing device, and more particularly to such a device in which positional deviation resulting from the presence of dead zones has been corrected.
2. Description of the Prior Art
It is usually the case with an automatic control device that an increase in its control sensitivity results in oscillations of a control system such as motors, gears and the like.
To prevent this, dead zones which are not responsive to the automatic control operation have heretofore been introduced into such systems. Likewise, in an automatic polarization analysing device (ellipsometer), the presence of such dead zones results in the production of positional deviations which, in turn, have led to failure to provide high accuracy in indications of azimuth and phase angles.